Long Term Objective: Finalize, following Phase I findings and through a well-designed Phase II research program, the testing and development of an innovative and highly-marketable motion/vibration product with proven applicable therapeutic properties that will soothe fussing and crying infants diagnosed as having colic. Colic incidence estimates range from 9 to 23% of the 1-3 month old population, with few effective treatments available. Specific Aim: a) Demonstrate optimal effectiveness of motion simulation (i.e., simulation of car motion)/vibration in soothing colicky infants; b) Optimize technical aspects and commercial application modes for existing prototypes/vibration ranges; c) Supplementary aim: Determine possible synergistic effect of motion with auditory stimulation and isolate the latter's contribution. METHODOLOGY: Experiment I (60 subjects): Test effectiveness of motion simulation (and supplementary aim) using a highly-structured procedure with a factorial design and time sampled behavioral outcome measures of infant response. Experiment II (40 subjects): a) Examine long-term effectiveness (permanency) of motion in a 23-day study with infant behavioral responses recorded by the mother while b) Measuring parental stress associated with infant colic/fussiness and prototype usage modes. Expected findings will derive effective marketing parameters for a product that will ease colic and incorporate the following benefits: Minimization of 1) infant pain; 2) drug utilization; 3) colic abuse; 4) family stress; 5) pediatrician's time devoted to colic.